From 5c79c74f6bbc5dd99bd6c6f4db70b451f54de5da Mon Sep 17 00:00:00 2001 From: jlh Date: Sun, 14 Jun 2015 07:47:18 +0000 Subject: NetBSD commit log: Use a constant array for the MIB. Newer LLVM decided that mib[] warranted stack protections, with the obvious crash after the setup was done. As a positive side effect, code size shrinks a bit. I'm not sure why this hasn't bitten us yes, but it is certainly possible and there are no real drawbacks to this change anyway. Submitted by: pfg Obtained from: NetBSD MFC after: 1 week --- lib/libc/sys/stack_protector.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) (limited to 'lib/libc/sys/stack_protector.c') diff --git a/lib/libc/sys/stack_protector.c b/lib/libc/sys/stack_protector.c index ed7d635..cd5f166 100644 --- a/lib/libc/sys/stack_protector.c +++ b/lib/libc/sys/stack_protector.c @@ -41,8 +41,8 @@ __FBSDID("$FreeBSD$"); #include #include "libc_private.h" -extern int __sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, - void *newp, size_t newlen); +extern int __sysctl(const int *name, u_int namelen, void *oldp, + size_t *oldlenp, void *newp, size_t newlen); long __stack_chk_guard[8] = {0, 0, 0, 0, 0, 0, 0, 0}; static void __guard_setup(void) __attribute__((__constructor__, __used__)); @@ -54,7 +54,7 @@ void __chk_fail(void); static void __guard_setup(void) { - int mib[2]; + static const int mib[2] = { CTL_KERN, KERN_ARND }; size_t len; int error; @@ -65,12 +65,9 @@ __guard_setup(void) if (error == 0 && __stack_chk_guard[0] != 0) return; - mib[0] = CTL_KERN; - mib[1] = KERN_ARND; - len = sizeof(__stack_chk_guard); - if (__sysctl(mib, 2, __stack_chk_guard, &len, NULL, 0) == -1 || - len != sizeof(__stack_chk_guard)) { + if (__sysctl(mib, nitems(mib), __stack_chk_guard, &len, NULL, 0) == + -1 || len != sizeof(__stack_chk_guard)) { /* If sysctl was unsuccessful, use the "terminator canary". */ ((unsigned char *)(void *)__stack_chk_guard)[0] = 0; ((unsigned char *)(void *)__stack_chk_guard)[1] = 0; -- cgit v1.1